Not go a bundle on somebody/something
Definition 1 of 1
Pro Tip 1/3British idiom
Primarily used by British English speakers, may not be understood in other English-speaking regions. 
She doesn't go a bundle on cricket—it's more of a British thing, isn't it?
Pro Tip 2/3Mild Dislike
Expresses a subtle, non-aggressive form of disinterest or mild dislike towards something or someone. 
I don't go a bundle on spinach, but I'll eat it if there's no other option.
Pro Tip 3/3Colloquial Use
This phrase is casual and more likely to be used in informal conversation rather than in formal writing. 
We don't go a bundle on the new manager's policies, do we?